Villalba L, Hicks J E, Adams E M, Sherman J B, Gourley M F, Leff R L, Thornton B C, Burgess S H, Plotz P H, Miller F W
National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, Maryland, USA.
Arthritis Rheum. 1998 Mar;41(3):392-9. doi: 10.1002/1529-0131(199803)41:3<392::AID-ART3>3.0.CO;2-X.
To assess the clinical usefulness of 2 novel therapies for treatment-resistant myositis.
Thirty patients with refractory myositis, of whom 25 had an inadequate or no response to previous cytotoxic therapy, were randomized to begin either a combination of weekly oral methotrexate and daily azathioprine (MTX/AZA) or intravenous methotrexate with leucovorin rescue (I.V. MTX) every 2 weeks for 6 months. Crossover to the alternate therapy occurred according to defined rules; evaluations of muscle strength and functional abilities were performed at the beginning, and after 3 and 6 months, of each treatment.
Of the 15 patients initially randomized to oral MTX/AZA, 8 improved with oral therapy and 1 improved with I.V. MTX during the crossover period. Of the 15 patients initially randomized to I.V. MTX therapy, 3 improved with the I.V. therapy and 4 with the oral combination during the crossover period. Although the study lacked the power to directly compare both treatments, intention-to-treat analysis showed a trend in favor of those patients who first received oral combination therapy (P = 0.025). There were 0.09 adverse events per patient-month with oral combination therapy and 0.16 per patient-month with I.V. therapy (P = 0.09).
Combination oral MTX/AZA may benefit patients with treatment-resistant myositis, including those who previously had inadequate responses to either MTX or AZA alone. I.V. MTX with leucovorin rescue may also benefit some patients with refractory myositis.
